No matter how many times I try to restart I am faced with diarrhea, stomach upset, and difficulty sleeping seemingly because my intestinal track seems to be in digesting mode all night long. It is hard to describe. I do think I have a lot of dreams while taking it as well. I am now starting back at 500 mg every other day. Additionally, I can tell it is still in my system the next day after taking it (meaning my day off), because if feel very cold all day long. By the way, feeling cold is the way I used to feel when I was in my teens, twenties, and thirties naturally. I didn't realize that feeling had gone away in my forties until I started taking metformin and the state of living while feeling colder than everyone else in the room came back.